The present invention relates generally to radiofrequency devices and more specifically to a radiofrequency identification and location system capable of locating and identifying remote objects with embedded radiofrequency (RF) transceiving functions with the aid of a Tracking Transceiver.
Current autonomous RF tracking technology is based on the received signal strength indicator (RSSI) method where the master tracker receives the signal strength from the tracked object and homes in to it as the RSSI increases. The RSSI is affected by many factors such as attenuation by intervening objects, foliage for example, that make the RSSI to vary too much to provide an accurate measurement of the distance. Other factors include the Tracking Transceiver antenna patterns that may make that signal to vary by at least 1 dB resulting in the same distance inaccuracies. The system described herein is based on the transmission of signal pairs where the Tracking Transceiver sends a pseudorandom noise (PN) coded signal and the Remote Transceiver responds with a similar signal assigned to the Tracking Transceiver. The Tracking Transceiver in turn measures the delay of the signal pair to get an accurate measurement of the Remote Transceiver distance as well as its identity.